Submission #374527

#	Time	Username	Problem	Language	Result	Execution time	Memory
374527		Aryan_Raina	Gondola (IOI14_gondola)	C++14	75 / 100	69 ms	4972 KiB

gondola

#include "gondola.h"
#include <bits/stdc++.h>

using namespace std;

#define ll long long

const ll MOD = 1e9+9;

int valid(int n, int a[]) {
    int rr = -1;
    set<int> vis;
    for (int i = 0; i < n; i++) {
    	if (vis.count(a[i])) return 0;
    	vis.insert(a[i]);
        if (a[i] <= n) {
            if (rr == -1) rr = i;
            if ((n + a[i] - a[rr]) % n != (n + i - rr) % n) return 0;
        }
    }
    return 1;
}

//----------------------

int replacement(int n, int a[], int replacementSeq[]) {
	int rr = -1;
	for (int i = 0; i < n; i++) {
		if (a[i] <= n) {
			rr = i; break;
		}
	}
	vector<array<int,2>> rep;
	for (int i = 0; i < n; i++) {
		if (a[i] > n) {
			int x = (a[rr] + i - rr + n) % n;
			if (x == 0) x = n;
			rep.push_back({a[i], x});
		}
	}
	sort(rep.begin(), rep.end());
	int ind = 0, last = n+1;
	for (int i = 0; i < rep.size(); ++i) {
		replacementSeq[ind++] = rep[i][1];
		last++;
		for (; last <= rep[i][0]; ++last) replacementSeq[ind++] = last-1;
	}
	return ind;
}

//----------------------
ll modpow(ll a, ll b) {
	ll res = 1;
	while (b) {
		if (b & 1) res = (res * a)%MOD;
		a = (a * a)%MOD;
		b>>=1;
	}
	return res;
}

ll fact(ll a) {
	int res = 1;
	for (int i = 1; i <= a; ++i) res = (res*i)%MOD;
	return res;
}

int countReplacement(int n, int a[]) {
	if (!valid(n, a)) return 0;
	vector<int> rep;
	for (int i = 0; i < n; i++) {
		if (a[i] > n) {
			rep.push_back(a[i]);
		}
	}
	sort(rep.begin(), rep.end());
	ll ans = 1, last = n+1;
	int sz = rep.size();
	for (int i = 0; i < sz; i++) {
		ans = (ans * modpow(sz-i, rep[i] - last)) % MOD;
		last = rep[i]+1;
	}
	if (rep.size() == n) {
		ans = (ans * fact(n)) % MOD;
	}
	return ans;
}

Compilation message (stderr)

gondola.cpp: In function 'int replacement(int, int*, int*)':
gondola.cpp:43:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<int, 2> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   43 |  for (int i = 0; i < rep.size(); ++i) {
      |                  ~~^~~~~~~~~~~~
gondola.cpp: In function 'int countReplacement(int, int*)':
gondola.cpp:83:17: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   83 |  if (rep.size() == n) {
      |      ~~~~~~~~~~~^~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 10 / 10
• Subtask 4: 5 / 5
• Subtask 5: 10 / 10
• Subtask 6: 20 / 20
• Subtask 7: 5 / 5
• Subtask 8: 15 / 15
• Subtask 9: 0 / 15
• Subtask 10: 0 / 10